[PATCH] char/tpm: use msleep(), clean-up timers,
The TPM driver unnecessarily uses timers when it simply needs to maintain a
maximum delay via time_before(). msleep() is used instead of
schedule_timeout() to guarantee the task delays as expected. While
compile-testing, I found a typo in the driver, using tpm_chp instead of
tpm_chip. Remove the now unused timer callback function and change
TPM_TIMEOUT's units to milliseconds. Patch is compile-tested.
Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Acked-by: Kylene Hall <kjhall@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/char/tpm/tpm_nsc.c b/drivers/char/tpm/tpm_nsc.c
index 9cce833a..6e5ffca 100644
--- a/drivers/char/tpm/tpm_nsc.c
+++ b/drivers/char/tpm/tpm_nsc.c
@@ -55,10 +55,7 @@
*/
static int wait_for_stat(struct tpm_chip *chip, u8 mask, u8 val, u8 * data)
{
- int expired = 0;
- struct timer_list status_timer =
- TIMER_INITIALIZER(tpm_time_expired, jiffies + 10 * HZ,
- (unsigned long) &expired);
+ unsigned long stop;
/* status immediately available check */
*data = inb(chip->vendor->base + NSC_STATUS);
@@ -66,17 +63,14 @@
return 0;
/* wait for status */
- add_timer(&status_timer);
+ stop = jiffies + 10 * HZ;
do {
- set_current_state(TASK_UNINTERRUPTIBLE);
- schedule_timeout(TPM_TIMEOUT);
+ msleep(TPM_TIMEOUT);
*data = inb(chip->vendor->base + 1);
- if ((*data & mask) == val) {
- del_singleshot_timer_sync(&status_timer);
+ if ((*data & mask) == val)
return 0;
- }
}
- while (!expired);
+ while (time_before(jiffies, stop));
return -EBUSY;
}
@@ -84,10 +78,7 @@
static int nsc_wait_for_ready(struct tpm_chip *chip)
{
int status;
- int expired = 0;
- struct timer_list status_timer =
- TIMER_INITIALIZER(tpm_time_expired, jiffies + 100,
- (unsigned long) &expired);
+ unsigned long stop;
/* status immediately available check */
status = inb(chip->vendor->base + NSC_STATUS);
@@ -97,19 +88,16 @@
return 0;
/* wait for status */
- add_timer(&status_timer);
+ stop = jiffies + 100;
do {
- set_current_state(TASK_UNINTERRUPTIBLE);
- schedule_timeout(TPM_TIMEOUT);
+ msleep(TPM_TIMEOUT);
status = inb(chip->vendor->base + NSC_STATUS);
if (status & NSC_STATUS_OBF)
status = inb(chip->vendor->base + NSC_DATA);
- if (status & NSC_STATUS_RDY) {
- del_singleshot_timer_sync(&status_timer);
+ if (status & NSC_STATUS_RDY)
return 0;
- }
}
- while (!expired);
+ while (time_before(jiffies, stop));
dev_info(&chip->pci_dev->dev, "wait for ready failed\n");
return -EBUSY;